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Exoskeletons are a defining character of all arthropods that provide physical support for their segmented bodies and appendages as well as protection from the environment and predation. This ubiquitous yet evolutionarily variable feature has been instrumental in facilitating the adoption of a variety of lifestyles and the exploitation of ecological niches across all environments. Throughout the radiation that produced the more than one million described modern species, adaptability afforded by segmentation and exoskeletons has led to a diversity that is unrivalled amongst animals. However, because of the limited extensibility of exoskeleton chitin and cuticle components, they must be periodically shed and replaced with new larger ones, notably to accommodate the growing individuals encased within. Therefore, arthropods grow discontinuously by undergoing periodic moulting events, which follow a series of steps from the preparatory pre-moult phase to ecdysis itself and post-moult maturation of new exoskeletons. Each event represents a particularly vulnerable period in an arthropod's life cycle, so processes must be tightly regulated and meticulously executed to ensure successful transitions for normal growth and development. Decades of research in representative arthropods provide a foundation of understanding of the mechanisms involved. Building on this, studies continue to develop and test hypotheses on the presence and function of molecular components, including neuropeptides, hormones, and receptors, as well as the so-called early, late, and fate genes, across arthropod diversity. Here, we review the literature to develop a comprehensive overview of the status of accumulated knowledge of the genetic toolkit governing arthropod moulting. From biosynthesis and regulation of ecdysteroid and sesquiterpenoid hormones, to factors involved in hormonal stimulation responses and exoskeleton remodelling, we identify commonalities and differences, as well as highlighting major knowledge gaps, across arthropod groups. We examine the available evidence supporting current models of how components operate together to prepare for, execute, and recover from ecdysis, comparing reports from Chelicerata, Myriapoda, Crustacea, and Hexapoda. Evidence is generally highly taxonomically imbalanced, with most reports based on insect study systems. Biases are also evident in research on different moulting phases and processes, with the early triggers and late effectors generally being the least well explored. Our synthesis contrasts knowledge based on reported observations with reasonably plausible assumptions given current taxonomic sampling, and exposes weak assumptions or major gaps that need addressing. Encouragingly, advances in genomics are driving a diversification of tractable study systems by facilitating the cataloguing of putative genetic toolkits in previously under-explored taxa. Analysis of genome and transcriptome data supported by experimental investigations have validated the presence of an "ultra-conserved" core of arthropod genes involved in moulting processes. The molecular machinery has likely evolved with elaborations on this conserved pathway backbone, but more taxonomic exploration is needed to characterise lineage-specific changes and novelties. Furthermore, linking these to transformative innovations in moulting processes across Arthropoda remains hampered by knowledge gaps and hypotheses based on untested assumptions. Promisingly however, emerging from the synthesis is a framework that highlights research avenues from the underlying genetics to the dynamic molecular biology through to the complex physiology of moulting.
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A new species of dung beetle, Proagoderus mabuensis Daniel, Josso, Nganhane & Strmpher, new species from Mount Mabu, northern Mozambique, is described, diagnosed, and illustrated. We provide a morphological comparison between the new species and a similar species from Mount Namuli, Mozambique, Proagoderus camiadei Josso, 2014. Both species belong to the Proagoderus dives (Harold, 1877) species-group. Furthermore, we provide an updated checklist of all known members of the dives species-group.
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Besouros , Animais , MoçambiqueRESUMO
Circularity confers protection to viral genomes where linearity falls short, thereby fulfilling the form follows function aphorism. However, a shift away from morphology-based classification toward the molecular and ecological classification of viruses is currently underway within the field of virology. Recent years have seen drastic changes in the International Committee on Taxonomy of Viruses' operational definitions of viruses, particularly for the tailed phages that inhabit the human gut. After the abolition of the order Caudovirales, these tailed phages are best defined as members of the class Caudoviricetes. To determine the epistemological value of genome topology in the context of the human gut virome, we designed a set of seven experiments to assay the impact of genome topology and representative viral selection on biological interpretation. Using Oxford Nanopore long reads for viral genome assembly coupled with Illumina short-read polishing, we showed that circular and linear virus genomes differ remarkably in terms of genome quality, GC skew, transfer RNA gene frequency, structural variant frequency, cross-reference functional annotation (COG, KEGG, Pfam, and TIGRfam), state-of-the-art marker-based classification, and phage-host interaction. Furthermore, the disparity profile changes during dereplication. In particular, our phage-host interaction results demonstrated that proportional abundances cannot be meaningfully compared without due regard for genome topology and dereplication threshold, which necessitates the need for standardized reporting. As a best practice guideline, we recommend that comparative studies of the human gut virome always report the ratio of circular to linear viral genomes along with the dereplication threshold so that structural and functional metrics can be placed into context when assessing biologically relevant metagenomic properties such as proportional abundance.
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Bacteriófagos , Viroma , Humanos , Viroma/genética , Genoma Viral , Bacteriófagos/genética , Metagenoma , BioensaioRESUMO
Onthophagus mabuensis Daniel, Strümpher & Josso, new species, is diagnosed, described and illustrated from Mount Mabu, which is situated in north-central Mozambique. Morphological comparison is made between this new forest species and similar species from Malawi and Zambia in group 3 of Onthophagus Latreille, 1802, as classified by d'Orbigny (1913). In addition, we provide a checklist of all known group 3 species.
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Besouros , Animais , Besouros/anatomia & histologia , MoçambiqueRESUMO
The loss of flight is common in the keratin beetle genus Phoberus Macleay, 1819 (Coleoptera: Trogidae)-20 out of the 49 species in this genus exhibit metathoracic-wing reduction in various degrees rendering them flightless. In this paper another flightless species, Phoberus villeti Strümpher, new species, is described and illustrated from the Amathole mountains in the Eastern Cape Province of South Africa. The new species is micropterous having tightly fused elytra (only wing rudiments visible), rounded humeral angles and a characteristic rounded body shape. However, it is most notable for its large size (~12 mm) and the distinctive tufts of yellow setae present on the elytra.
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Besouros , Animais , África do SulRESUMO
A new species of keratin beetle from Western India, Omorgus (Omorgus) khandesh Strümpher & Kalawate, new species, is described and illustrated. The new species is morphologically most similar to O. (O.) rimulosus (Haaf, 1957). The latter is redescribed and illustrated to enable accurate recognition of both species. Based on this work the following taxonomic changes are proposed: Three species are transferred from the subgenus Afromorgus Scholtz, 1986 to the nominotypical subgenus: O. (O.) inclusus (Walker 1858), O. (O.) maissouri (Haaf, 1945a) and O. (O.) rimulosus (Haaf, 1957). Lastly, we include an annotated catalogue of the species of the nominotypical subgenus Omorgus known from the Oriental and Palaearctic regions.
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Besouros , Animais , ÍndiaRESUMO
Single-cell ribonucleic acid sequencing (scRNA-seq) enables the quantification of gene expression at the transcriptomic level with single-cell resolution, enhancing our understanding of cellular heterogeneity. However, the excessive missing values present in scRNA-seq data hinder downstream analysis. While numerous imputation methods have been proposed to recover scRNA-seq data, high imputation performance often comes with low or no interpretability. Here, we present IGSimpute, an accurate and interpretable imputation method for recovering missing values in scRNA-seq data with an interpretable instance-wise gene selection layer (GSL). IGSimpute outperforms 12 other state-of-the-art imputation methods on 13 out of 17 datasets from different scRNA-seq technologies with the lowest mean squared error as the chosen benchmark metric. We demonstrate that IGSimpute can give unbiased estimates of the missing values compared to other methods, regardless of whether the average gene expression values are small or large. Clustering results of imputed profiles show that IGSimpute offers statistically significant improvement over other imputation methods. By taking the heart-and-aorta and the limb muscle tissues as examples, we show that IGSimpute can also denoise gene expression profiles by removing outlier entries with unexpectedly high expression values via the instance-wise GSL. We also show that genes selected by the instance-wise GSL could indicate the age of B cells from bladder fat tissue of the Tabula Muris Senis atlas. IGSimpute can impute one million cells using 64 min, and thus applicable to large datasets.
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Análise da Expressão Gênica de Célula Única , Software , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Perfilação da Expressão Gênica , Transcriptoma , Análise por ConglomeradosRESUMO
Mabu Forest in northern-central Mozambique harbours the largest continuous block of rainforest remaining in southern Africa. Also, the region is known for its exceptional levels of biodiversity, including a high level of endemism. Several new taxa of plants and animals have been discovered from previous biological expeditions. Last year, we conducted the first dung beetle exploration in the regionwhere almost half of the dung beetle species collected are new to science. In this paper, we describe, diagnose and illustrate Pedaria ricardogutai Daniel, Strmpher & Josso, new species. We compared the new species to the most morphologically similar species, Pedaria sudrei Josso & Prvost, 2003. We also provide an annotated checklist of 17 species of Pedaria Laporte, 1832, recorded from Mozambique, including type localities and distribution records.
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Besouros , Animais , Moçambique , Biodiversidade , FlorestasRESUMO
BACKGROUND: The WHO recommends TB preventive treatment (TPT) for people living with HIV, including pregnant women. Uptake of this policy recommendation in this subpopulation and country alignment with WHO guidance is unclear.METHODS: We conducted a policy review in 38 WHO high TB and TB-HIV burden countries to assess if the uptake of TPT policy among pregnant women living with HIV was in line with the WHO´s 2018 Updated and Consolidated Guidelines for Programmatic Management for LTBI. Data sources included TB national guidelines and HIV/AIDS/ART national guidelines, complemented by results from a previous survey on policy uptake held at the WHO.RESULTS: Uptake of WHO policy to provide TB preventive treatment among women with HIV accessing antenatal care was moderate: 64% (23 of 36 countries) explicitly recommended at least one clinical guideline or policy recommendation on screening, testing or treatment of LTBI among pregnant women living with HIV. There was considerable variation between countries on the stages in pregnancy that TPT should be provided. Two countries (5%) provided clinical monitoring recommendations for pregnant women.CONCLUSIONS: There is moderate uptake of TPT policy for pregnant women with HIV. Failure to provide TPT as part of antenatal or prevention of mother-to-child services is a missed opportunity for TB control.
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Infecções por HIV , Tuberculose , Feminino , Humanos , Gravidez , Infecções por HIV/tratamento farmacológico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Programas de Rastreamento , Gestantes , Tuberculose/prevenção & controleRESUMO
Tok-tokkies are one of the most iconic lineages within Tenebrionidae. In addition to containing some of the largest darkling beetles, this tribe is recognized for its remarkable form of sexual communication known as substrate tapping. Nevertheless, the phylogenetic relationships within the group remain poorly understood. This study investigates the usefulness of female terminalia morphology for delimiting Sepidiini and reconstructing relationships among it. Data on the structure of the ovipositors, genital tubes and spicula ventrali have been generated for >200 species representing 28 Pimeliinae tribes. This dataset was used in a comparative analysis at the subfamilial level, which resulted in recognition of several unique features of tok-tokkie terminalia. Additionally, new features linking phenotypically challenging tribes also were recovered (Cryptochilini + Idisiini + Pimeliini). Secondly, 23 characters linked to the structure of female terminalia were defined for tok-tok beetles. Cladistic analysis demonstrates the nonmonophyletic nature of most of the recognized subtribes. The morphological dataset was analysed separately and in combination with available molecular data (CAD, Wg, cox1, cox2, 28S). All obtained topologies were largely congruent, supporting the following changes: Palpomodina Kaminski & Gearner subtr.n. is erected to accommodate the genera Namibomodes and Palpomodes; Argenticrinis and Bombocnodulus are transferred from Hypomelina to Molurina; 153 species and subspecies previously classified within Psammodes are distributed over three separate genera (Mariazofia Kaminski nom.n., Piesomera stat.r., Psammodes sens.n.). Psammodes sklodowskae Kaminski & Gearner sp.n. is described. Preliminary investigation of the ovipositor of Mariazofia basuto (Koch) comb.n. was carried out with the application of microcomputed tomography, illuminating the muscular system as a reliable reference point for recognizing homologous elements in highly modified ovipositors.
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Besouros , Animais , Feminino , Filogenia , Microtomografia por Raio-X , Sorogrupo , GenitáliaRESUMO
Silvaphilus joselmae Daniel, Strmpher Deschodt, new species is diagnosed and described from the Cederberg Mountains, South Africa. The tribal affiliation of Silvaphilus Roets Oberlander, 2010 is briefly discussed. We revise some generic characters and update the key for the species and genera in the tribe Endroedyolini Davis, Deschodt Scholtz, 2019. We also provide a distribution map of the two Silvaphilus species.
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Besouros , Animais , Fezes , África do SulRESUMO
A new species of dung beetle, Stiptopodius brancoi Strmpher Daniel, new species, from Namibia, is diagnosed, described, and illustrated. The new species is the first Stiptopodius recorded from the country and belong to the singularis species group. A revised key as well as a checklist of Stiptopodius species recorded from the African continent are provided.
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Besouros , Animais , Pradaria , NamíbiaRESUMO
The genus Synalpheus is a cosmopolitan clade of marine shrimps found in most tropical regions. Species in this genus exhibit a range of social organizations, including pair-forming, communal breeding, and eusociality, the latter only known to have evolved within this genus in the marine realm. This study examines the complete mitochondrial genomes of seven species of Synalpheus and explores differences between eusocial and non-eusocial species considering that eusociality has been shown before to affect the strength of purifying selection in mitochondrial protein coding genes. The AT-rich mitochondrial genomes of Synalpheus range from 15,421 bp to 15,782 bp in length and comprise, invariably, 13 protein-coding genes (PCGs), two ribosomal RNA genes, and 22 transfer RNA genes. A 648 bp to 994 bp long intergenic space is assumed to be the D-loop. Mitochondrial gene synteny is identical among the studied shrimps. No major differences occur between eusocial and non-eusocial species in nucleotide composition and codon usage profiles of PCGs and in the secondary structure of tRNA genes. Maximum likelihood phylogenetic analysis of the complete concatenated PCG complement of 90 species supports the monophyly of the genus Synalpheus and its family Alpheidae. Moreover, the monophyletic status of the caridean families Alvinocaridae, Atyidae, Thoridae, Lysmatidae, Palaemonidae, and Pandalidae within caridean shrimps are fully or highly supported by the analysis. We therefore conclude that mitochondrial genomes contain sufficient phylogenetic information to resolve relationships at high taxonomic levels within the Caridea. Our analysis of mitochondrial genomes in the genus Synalpheus contributes to the understanding of the coevolution between genomic architecture and sociality in caridean shrimps and other marine organisms.
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Decápodes/classificação , Genômica/métodos , Mitocôndrias/genética , Animais , Uso do Códon , Decápodes/genética , Tamanho do Genoma , Genoma Mitocondrial , Filogenia , RNA de Transferência/genética , Seleção GenéticaRESUMO
Among the southern African Trogidae, Trox fumarius Haaf, 1953 is presently considered a junior subjective synonym of Phoberus cyrtus (Haaf, 1953). The availability of more specimens than were seen by previous workers, coupled with thorough removal of cuticular dirt and accumulated debris, allowed in-depth morphological study of these nominal taxa and reassessment of their synonymy. Consistent differences in external morphology and in aedeagal structure are observed. Trox fumarius is removed from synonymy with Phoberus cyrtus, reinstated as a separate species, and transferred to the genus Phoberus MacLeay, 1819. Both species are diagnosed and redescribed. Photographs of their holotypes and of cleaned specimens illustrate them. The distributions of these two putatively sister species are discussed along with their probable habitat associations. The species are allopatric and have non-overlapping associations with biomes and habitats. Phoberus cyrtus is reported from Botswana for the first time. The importance of properly cleaning terricolous beetles covered with dirt and debris that obscure taxonomic features is emphasised and guidelines to achieve this are presented.
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Besouros , África Austral , Distribuição Animal , Animais , Ecossistema , QueratinasRESUMO
Haroldius lyleae Daniel, Strmpher Snll, new species, is described and illustrated from South Africa. The new species can be easily distinguished from other species of the genus by its notable triangular clypeus lacking the distinctive mid-anterior indentation and denticles present in other Haroldius Boucomont, 1914 species. Monomorium albopilosum Emery, 1895 (Hymenoptera: Formicidae: Myrmicinae) is recorded as a possible ant host of the new species. Haroldius modestus (Janssens, 1953) is recorded from Zimbabwe for the first time, and Haroldius convexus (Philips Scholtz, 2000) is now recorded from the North West and KwaZulu-Natal Provinces of South Africa as well.
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Formigas , Besouros , África Austral , Animais , África do SulRESUMO
BACKGROUND: In patients with limited communication skills, the use of conventional scales or external assessment is only possible to a limited extent or not at all. Multimodal pain recognition based on artificial intelligence (AI) algorithms could be a solution. OBJECTIVE: Overview of the methods of automated multimodal pain measurement and their recognition rates that were calculated with AI algorithms. METHODS: In April 2018, 101 studies on automated pain recognition were found in the Web of Science database to illustrate the current state of research. A selective literature review with special consideration of recognition rates of automated multimodal pain measurement yielded 14 studies, which are the focus of this review. RESULTS: The variance in recognition rates was 52.9-55.0% (pain threshold) and 66.8-85.7%; in nine studies the recognition rate was ≥80% (pain tolerance), while one study reported recognition rates of 79.3% (pain threshold) and 90.9% (pain tolerance). CONCLUSION: Pain is generally recorded multimodally, based on external observation scales. With regard to automated pain recognition and on the basis of the 14 selected studies, there is to date no conclusive evidence that multimodal automated pain recognition is superior to unimodal pain recognition. In the clinical context, multimodal pain recognition could be advantageous, because this approach is more flexible. In the case of one modality not being available, e.g., electrodermal activity in hand burns, the algorithm could use other modalities (video) and thus compensate for missing information.
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Inteligência Artificial , Medição da Dor , Dor , Algoritmos , Humanos , Limiar da DorRESUMO
BACKGROUND: Prostate-specific membrane antigen (PSMA) SPECT imaging in prostate cancer (PCa) could be a valuable alternative in regions where access to PSMA-PET imaging is restricted. [99mTc]Tc-PSMA-I&S is a new 99mTc-labeled PSMA-targeting SPECT agent, initially developed for radio-guided surgery. We report on the diagnostic use of [99mTc]Tc-PSMA-I&S-SPECT/CT in PCa. RESULTS: [99mTc]Tc-PSMA-I&S-SPECT/CT was performed and evaluated in 210 outpatients with PCa at a single center. Patients were imaged for biochemical recurrence (BCR, n = 152, mean PSA 8.7 ng/ml), for primary staging of high-risk PCa (n = 12, mean PSA 393 ng/ml), and restaging in advanced recurrent PCa (n = 46, mean PSA 101.3 ng/ml). Number and location of positive lesions were determined for the different subgroups. For BCR, detection rates were calculated, defined as the proportion of scans with at least one PSMA-positive lesion. PSMA positive lesions were detected in 65.2% of all 210 patients. Tumor tissue was mainly detected in lymph nodes (59%), in the bone (42%), and in the prostate (fossa) (28%). In the subgroup of patients referred for detection of BCR the detection rate increased from 20% at a PSA level < 1 ng/ml to 82.9% and 100% at PSA levels > 4 ng/ml and > 10 ng/ml, respectively. In the subgroup of high-risk patients referred for primary staging, 42% demonstrated metastatic disease. Restaging of advanced recurrent PCa revealed detectability of PSMA positive tumor lesions in 85% of the scans. CONCLUSIONS: [99mTc]Tc-PSMA-I&S-SPECT/CT was useful in PSMA-targeted imaging of PCa at various clinical stages. At low PSA levels (< 4 ng/ml), detection rates of [99mTc]Tc-PSMA-I&S-SPECT/CT in BCR are clearly inferior to data reported for PET-imaging and should thus only be considered for lesion detection if imaging with PET is unavailable. However, at higher PSA levels (> 4 ng/ml) [99mTc]Tc-PSMA-I&S-SPECT/CT provides high detection rates in BCR. [99mTc]Tc-PSMA-I&S-SPECT/CT can also be used for primary staging and for restaging of advanced recurrent PCa. However, further studies are needed to assess the clinical value in these indications.